Abstract

Introduction

Neo-adjuvant chemotherapy prior to surgical resection is a relatively new strategy for treating locally advanced colon cancer. This multicenter study aims to identify the surgical and oncological complications and analyze survival outcomes in patients who were treated with this regimen.

Methods

The records of all patients who received neo-adjuvant therapy for locally advanced colon cancer in three dedicated colorectal centers between 2009 and 2014 were retrospectively reviewed. Patient and tumor characteristics, as well as surgery and chemotherapy related complications, and survival outcomes were collected.

Results

Twenty-eight patients underwent neo-adjuvant chemotherapy prior to surgery. All patients had clinically T4 locally advanced tumors without signs of distant metastases. Median age was 62 years (range 30-80) and the majority were female (n = 19; 68%). The majority of patients had an adenocarcinoma (n = 23; 89%), five patients had a mucinous subtype (11%). Tumors were localized in the sigmoid (n= 13; 46%) and the coecum (n = 8; 29%) or other parts of the colon (7; 25%). The main choice of chemotherapy was capecitabine in combination with oxaliplatin (n = 21, 75%), six patients received fluorouracil and oxaliplatin (21%) and one patient received capecitabine monotherapy. Additional targeted therapy was given in five patients (bevacizumab (n = 4) or panitumumab (n = 1)). Median number of cycles was 5.5 (range 1-17). Twenty-three patients (82%) experienced complications, of which seven were severe, CTCAE grade III or IV (e.g. bone marrow suppression, sepsis or liver failure). In eleven patients (39%) dose reduction of was necessary, mainly the dose of oxaliplatin. Eleven patients (39%) did not finish systemic therapy due to complications and surgery was put forward. In all patients resection of the tumor was performed and a complete resection (R0) was achieved in 25 patients (89%). Downsizing of the tumor was seen in eleven patients (39%) with a complete response in one patient. Seven patients (25%) suffered from postoperative complications necrosis of the Bricker bladder (grade III), and three anastomotic leakages (grade III). Mean follow-up was 21 months (range 1 – 64). Four patients (14%) developed locoregional recurrences, three patients (11%) were diagnosed with metachronous distant metastases and in one patient the location of recurrence was not specified. The 2-year overall survival was 76%.

Conclusion

A significant number of patients with clinical T4 locally advanced colon cancer showed downsizing after neo-adjuvant chemotherapy, making a complete resection possible in the majority of patients. This treatment strategy seems to be safe and feasible with good short and long-term results and should be considered in patients with locally advanced colon cancer.